Inspired by the developments of synthetic biology and the need for improved genetic tools to exploit cyanobacteria for the production of renewable bioproducts, we developed a versatile platform for the construction of broad-host-range vector systems. This platform includes the following features: (i) an efficient assembly strategy in which modules released from 3 to 4 donor plasmids or produced by polymerase chain reaction are assembled by isothermal assembly guided by short GC-rich overlap sequences. (ii) A growing library of molecular devices categorized in three major groups: (a) replication and chromosomal integration; (b) antibiotic resistance; (c) functional modules. These modules can be assembled in different combinations to construct a variety of autonomously replicating plasmids and suicide plasmids for gene knockout and knockin. (iii) A web service, the CYANO-VECTOR assembly portal, which was built to organize the various modules, facilitate the in silico construction of plasmids, and encourage the use of this system. This work also resulted in the construction of an improved broad-host-range replicon derived from RSF1010, which replicates in several phylogenetically distinct strains including a new experimental model strain Synechocystis sp. WHSyn, and the characterization of nine antibiotic cassettes, four reporter genes, four promoters, and a ribozyme-based insulator in several diverse cyanobacterial strains.

Two hundred and sixteen consecutive patients with MDS and abnormal karyotype treated with hypomethylating agents between 4/04 and 10/12 were reviewed. Median follow-up was 17 months. Using IWG criteria, best responses were complete response (CR) in 79 patients (37%), partial response (PR) in 4 (2%), and hematologic improvement (HI) in 10 (5%). Cytogenetic response (CyR) was achieved in 78 patients (36%): complete (CCyR) in 62 (29%) and partial in 16 (7%). CyR was achieved in 48 of 79 patients (61%) with CR, 1 of 14 (7%) with PR/HI, and in 29 of the 123 (24%) with no morphologic response. Median overall survival (OS) and leukemia-free survival (LFS) for patients with and without CCyR were 21 and 13 months (P = .007), and 16 and 9 months (P = .001), respectively. By multivariate analysis, the achievement of CCyR was predictive for better OS (HR = 2.1; P < .001). In conclusion, CyR occurs at a rate of 36% (complete in 29%) in patients with MDS treated with HMA and is not always associated with morphological response. The achievement of CCyR is associated with survival improvement and constitutes a major predictive factor for outcome particularly in patients without morphologic response. Therefore, the achievement of CCyR should be considered a milestone in the management of patients with MDS.